1) Field of the Invention
The present invention relates generally to agricultural implements and, more specifically, to a leveling system for a disk or similar implement.
2) Related Art
Disks typically have front and rear gangs mounted on a frame having a forward hitch adapted for connecting to a tractor. Disking performance, transport stability and transport levelness of a disk are affected by many factors, including tractor drawbar heights, field conditions, rear attachments, disk blade diameters, operating speed and operating depth. Many disks have a leveling system connected between the lift system and the hitch to compensate for changes in some of these factors. The leveling system, which usually includes a spring-loaded adjusting member connected to a bell crank, adjusts the front to rear loading on the implement to achieve a better soil profile in the tilled ground. However, a problem occurs when the disk is operating in certain soil conditions or when additional weight is applied to the rear of the machine via rear attachments such as harrows or hitches and the machine becomes rear-heavy. As a result, leveling of the soil while disking is a problem, and the soil profile is less than ideal. This problem is emphasized when the rear attachment on the disk is itself adjustable.
Various spring arrangements have been suggested for compensating for the rear heavy condition, but these have provided only limited relief. Often the spring biasing system fails to provide a positive transport stop and introduces some disk transport instability. Implement leveling during transport also has been troublesome with some of the systems.